A direct fluorescent signal transducer embedded in a DNA aptamer paves the way for versatile metal-ion detection

SENSORS AND ACTUATORS B-CHEMICAL

卷:304

Article

Raducanu, Vlad-Stefan¹  Rashid, Fahad¹  Zaher, Manal S.¹  Li, Yanyan¹  Merzaban, Jasmeen S.¹  Hamdan, Samir M.¹ 

[1] King Abdullah Univ Sci & Technol, Div Biol & Environm Sci & Engn, Thuwal 23955, Saudi Arabia

关键词: Potassium sensor;    DNA aptamer;    G-quadruplex;    Metal ion detection;    Fluorescent signal transducer;    Cy3 photoisomerization;   

DOI  :  10.1016/j.snb.2019.127376

来源: Elsevier

【 摘 要 】

Using DNA aptamers as sensors for metal ions provide a variety of applications in biology and industry. Many of these sensors are based on guanine-rich DNA sequences that undergo conformational changes upon metal-ion binding. However, these sensors require an exogenous reporter that can recognize such DNA conformational changes and transduce the signal. Here, we bypass the exogenous reporter by embedding a signal transducer in the guanine-rich DNA aptamer that measures directly the DNA conformational changes upon metal-ion binding. Our signal transducer is an environmentally sensitive Cy3 fluorescent dye that is internally coupled to the DNA aptamer. We demonstrate the applicability of our embedded-signal transducer approach using a known potassium-responding aptamer. We next demonstrate the versatility of this approach by designing an aptamer sensor that can detect potassium ions in the low micro-molar range and with high selectivity against a wide range of ions including sodium. The aptamer accurately measured potassium ions concentration in a variety of aqueous and biological test samples. Our embedded-signal transducer approach will pave the way for the development of aptamer sensors for a variety of ligands.

【 授权许可】

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